You cannot always blow dry your hair. Blow drying your hair every single day can be extremely damaging to your hair. Air drying can be a solution for jet-straight hair and unruly curls. Beauty expert Janet Fernandez tells you how you can blow dry your hair so that it never looks unruly and frizzy. For thin straight hair: If your hair is thin and straight reach for a leave-in conditioner. Spray the conditioner at the ends of your hair and distribute it through the strands. Your hair will look greasy if you apply the conditioner directly to the roots first.